Optical characterization and Judd-Ofelt analysis of Pr3+ ions in sol-gel derived zirconia/polyethylene glycol composite.

The photoluminescence characteristics of praseodymium (Pr 3+ ) doped zirconia/polyethylene glycol (ZrO 2 /PEG) samples were studied using optical absorption and emission spectra. The optical properties were theoretically analysed using standard and modified Judd-Ofelt (J-O) models. The oscillator strength of the observed transitions and J-O intensity parameters were calculated using these J-O models. The radiative properties such as radiative transition probability ( A T ), branching ratio ( β R ), stimulated emission cross-section ( σ e ) and gain band width ( σ e × Δ λ e f f ) for the excited states of Pr 3+ in ZrO 2 /PEG composite have been determined. The experimental branching ratios obtained from the emission spectra were compared with the theoretical values. The excitation spectra of Pr 3+ doped samples show overlapping of Pr 3+ excitation peak at 448 nm at the end of the broad excitation band of the host, indicating the charge transfer between the host and Pr 3+ ions. Luminescence decay analysis confirmed concentration quenching in the prepared samples and the lifetime values are found to be in the microsecond range. [ABSTRACT FROM AUTHOR]